System for programming a lock comprising contactless nfc communication means

ABSTRACT

The invention relates to a system including a lock ( 10 ) provided with electronic NFC transceiver circuits and electric circuits for controlling mechanical locking/unlocking members, and a portable telephone ( 16 ) provided with circuits for NFC mode of operation. The telephone comprises means for initializing the lock, said means including means for: downloading, from a remote site ( 20 ), an applet and elements required for initializing the lock; verifying, using the telephone, the identifier and the transport key stored in the lock against the downloaded ones; deactivating the transport key of the lock; loading, onto the lock, a unique random algorithm and a cryptographic key that have been downloaded; and generating a message notifying of the termination of the initialization of the lock.

The invention relates to locks controlled by means of a hand-held object acting as a key, typically in the form of a contactless badge or chip card, which cooperates with the lock by way of a non-galvanic mutual coupling of the NFC (Near Field Communication) type.

With such technology, the coupling between the hand-held object and the lock is made by varying a magnetic field produced by a coil (such technique being referred to as “induction process”). The lock comprises for that purpose an inductive circuit excited by an AC signal that produces a variable magnetic field, able to be detected over a range of at most a few centimeters. The hand-held object located within this range receives the energy of the field (which permits in particular the remote power supply of the hand-held object, the latter having generally no power source of its own) and modulates an inner charge. Such modulation, coded by various data coming from the hand-held object (identifier, encryption key, etc.), is then detected by the lock, which establishes the desired bidirectional communication.

Various coding and encryption techniques exist for securing the contactless communication between the hand-held object and the lock, and protecting the latter against any risk of fraud.

Such protection techniques use algorithms and keys that are implemented in the lock. However, to thwart any risk of fraud, in particular during the transport from the factory to the definitive location, the lock is not originally provided with all the security elements permitting the implementation of these techniques.

Initially, the locks are delivered with provisional cards referred to as “emergency cards”, which permit to operate the lock during the time required for the installation thereof, but which do not operate the most elaborate protection techniques; the cryptographic techniques used at this stage are used with a provisory (logical) key referred to as a “transport key”, also of temporary nature, or even with a limited service time.

Once the lock is installed, it has to be “programmed” so as to implement therein the algorithms, advanced cryptographic elements and definitive keys permitting to obtain the desired high level of security.

In practice, such programming is often difficult to perform, with risk of errors, even for the lock professionals and even more so for individual users that would desire to install and program their lock themselves. Such complexity and risk of errors are an obstacle to a wide diffusion of these NFC-type contactless locks, despite the numerous advantages they offer, in particular as regards the security.

The object of the invention is to propose a new technique for programming a NFC-type contactless lock, which is easy to implement, even by an uninitiated user, and which moreover does not require any specific material; while keeping a very high level of security all along the sequence of operations, from the transport from the manufacturing factory up to the final programming.

The principle of the invention consists in using for this programming step a portable telephone equipped with a NFC chip and a NFC antenna, with the telephone SIM card being used as an element for securing the data exchanges performed by NFC.

The exchanges between the telephone and the lock may be secured by means of a specific application of the “applet” type, previously downloaded by the telephone. Once loaded and activated, this applet will automatically implement the different steps required for programming the lock, such as downloading an encryption algorithm, keys, identifiers, . . . operable to ensure the lock programming in a perfectly secured manner.

An exemplary embodiment of the invention is described with reference to FIG. 1. In this figure, the reference number 10 designates the lock, which externally looks like a unitary element from which appears only a handle 12 and a target area 14 for the NFC communication, i.e. an area against which the hand-held object that acts as a key for opening the lock will have to be presented, wherein the object is a contactless card 16 provided with suitable circuits.

When the card 16 is approached, the lock produces an AC magnetic field in order to establish a bidirectional coupling for data exchange with the card 16. The lock may then interrogate this card, according to known techniques, to read therein identifiers, codes, data, authorizations, etc., stored in the memory of the card. These data are verified and, if they match, they control a motor for unlocking the mechanical elements of the lock.

To avoid any fraud attempt, such security techniques cannot be implemented in the lock in the state the latter is at the factory output, during the transport to the final site, and as long as the lock is not definitively installed.

It is only after the lock is installed that the complete security functions will be activated, by a so-called “programming” operation. Meanwhile, the lock can only be operated by means of a card referred to as an “emergency card”, which uses only simplified algorithms based on a provisional “transport key”.

The way this programming is characteristically performed according to the invention will now be described.

The programming is performed by means of a portable telephone 18 provided, in addition to the telephony circuits for data transmission and reception, with a NFC chip and an induction coil acting as an antenna. Those circuits enable the telephone to operate in an NFC mode, with the SIM card being used as a security element for the NFC communication.

The lock is identified by a non-modifiable unique identifier (hereinafter “the identifier”) that permits to recognize it between all the locks, such identifier being of similar nature as the international Mobile Equipment Identity, IMEI, identifier embedded in a GMS or UMTS mobile terminal for the unique and definitive identification of the equipment.

The first operation consists in downloading into the telephone an applet that will permit to automatically execute the sequence of steps required for programming the lock.

Such downloading follows a request sent by the telephone 18 to the remote site 20 of the lock manufacturer or manager, via the operator 22 of the mobile telephone network.

Once downloaded by the telephone 18, the applet is activated, which triggers the transmission from the remote site 20 to the telephone 18 of the different elements required for the programming of each lock, in particular: the recorded lock identifier (or the list of lock identifiers if there are several locks to be programmed), a unique random algorithm, a transport key, a cryptographic key, etc.

Once all these data are loaded into the telephone 18, the user just needs to present the telephone in front of the target area 14 of the lock to be programmed (or of each of the locks to be programmed) in order to establish the bidirectional NFC coupling between the telephone and the lock.

The telephone reads the identifier of the lock to which it is thus coupled: if the identifier read in the lock matches with the identifier received by the telephone from the remote site (or with one of the identifiers, in case there is a plurality of locks to be programmed), then the telephone determines the transport key associated with this identifier.

If the transport key of the lock corresponds to that determined by the telephone, the latter can then begin the actual lock programming process.

First, the telephone resets the lock, by deactivating the transport key and by making the emergency cards delivered with the lock inoperative.

Then, it uploads into the lock the elements required for implementing the security procedures, in particular the unique random algorithm and the definitive cryptographic key. The secured cryptographic procedure can then be activated.

During the execution of the programming process, the user can follow the operation progress by means of a progress bar displayed on the telephone screen.

Once all the operations are correctly executed, the applet generates a message for notifying the completion of the lock programming and displays this message on the telephone screen, indicating that the operation has been successfully performed.

If several locks have to be programmed, the list of the remaining locks to be programmed is displayed on the telephone screen. 

1. A system comprising: at least one lock (10) provided with electronic circuits for NFC transmission/reception and with electric circuits for the control of locking/unlocking mechanical elements, and a portable telephone (18) provided with circuits enabling it to operate in NFC mode, said system being characterized in that the telephone comprises means for performing an initial programming of the lock, said means including: means for downloading from a remote site an applet operable to automatically execute the sequence of next steps for the lock programming; means for downloading from the remote site the elements required for the lock programming, said elements including: a recorded lock identifier, a unique random algorithm, a transport key and a cryptographic key; means for establishing a bidirectional NFC coupling between the lock and the telephone; means for making the telephone verify the matching of the identifier and the transport key stored in the lock with the identifier and the transport key downloaded from the remote site; means for deactivating the transport key of the lock; means for uploading into the lock the unique random algorithm and the cryptographic key; and means for generating a message for notifying the completion of the lock programming. 